Hotpoint FF72 Fridge Temprature Problem

Ok, Here we go....

I have a FF72 The frezer is working ok at -22 and when the ff button is pressed it will drop even further. However the fridge is sitting at +22 (ambiant). when the button above the door is pressed you can hear the fan kick in, and stop when released. I presume by the fact that the freezer is working ok and the fan is working ok it is the thermistor at fault.

Can anyone tell me...

1. Where is the thermistor(s) responsible located?
2. The part No. for the thermistor(s)?
3. Is there anything that I have overlooked that could be responsible?

Thermistors are located in the freezer compartment behind back panel
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